When speaking in English with others (my second language), I barely
can talk and talk for a long time.  I always speak in short sentences
that straight to the point, or ask questions then have the other party
to talk.  Sometimes I rather send an email to the person than calling
them.  But when I speak in my first language with friends, I can
express myself easily and can be very talkative and caring.  How are
the underlying causes of my problems, and what are the solutions.

Well, your shyness can be caused by a number of factors.
- You simply don't know enough words to express yourself as you would
in your first language (I doubt that's what it is, but still)
- You're more comfortable speaking to people in your native language. 
- Your shyness' cause lies on a subconscious level. The only way to
overcome that is to talk. I would suggest maybe finding people you're
comfortable (or people who can bear talking) with and talking to them.
Some wine wouldn't hurt.

Hi natural100,

  Do you speak with native English speakers often? I believe if you
would practice as often as you can,with native English speakers, you
would gain confidence. Having confidence in yourself will actually
improve your speaking skills.

  A lot of my Latino friends have never learned English, even after 20
years in the US. Where we live, there are 6 Spanish language channels
on TV, at least 6 Spanish language radio stations, 4 Spanish language
newspapers, and most elementary schools have some degree of bi-lingual
classes. We have entire shopping districts, all Latino owned. My
friends get along nicely without learning English!

   Read English language newspapers and magazines, and watch English
language TV. Soap operas, while not great content, are usually slower
paced, are a good way to hear English too. (I learned a lot from
Spanish language "telenovelas".

  Don't worry if you make mistakes either. Many native English
speakers do not speak a second language, so the fact that you are able
to converse in a second language at all says a lot. You are far ahead
many English speakers!

  I began learning Spanish at the age of 7, after movng to Spain.
After my return to the US, I slowly lost much of my fluency, from
non-use. When I graduated from college and joined the work force, my 
Spanish helped me immensely. I too, felt nervous, especially when
using Spanish in a professional capacity.  I took a medical
interpreter's course, and was the only non-native speaker in my class.
When I realized most of my classmates made mistakes, in their own
language, I relaxed, and improved my own "flow" in Spanish. In fact, I
was the valedictorian, and spoke, unrehearsed, at our graduation.

  Be proud of yourself for getting as far as you are in a second language!

Hi natural00,

I answered a question that might be of interest to you... you'll
especially be interested in reading through to the end of my answer:
Methods to improve your pronounciation of the English Language:

English 
http://answers.google.com/answers/threadview?id=379226


Best regards,
tlspiegel

Vodka

On the bright side, it doesn't sound like you have Selective Mutism.
[Information Page: http://www.nlm.nih.gov/medlineplus/ency/article/001546.htm]

However, I noticed you seem comfortable when speaking your first
language with friends.
If you don't feel comfortable speaking your first language with
strangers, you may have social anxiety disorder.

You might also have a fear of speaking incorrectly.

My girlfriend is Polish and she learned English is less than a year. 
It still astounds me.  We found that whenever we could not express to
each other what we wanted to say we turned it into a game.  Example:

"I saw a deer in the forest today"

"What is a deer?"

"Bambi from Disney is a deer."

"Oh. ok. I know."

It sounds funny, and it is.  But it works.  Let the speaker know that
you do not speak wonderfully.  Ask questions and build your
vocabulary.  It gets to be fun and you will speak better English
quickly.  And be glad that you do not have to learn Polish!

It actually doesn't have to do with being shy... well maybe a little
it does... I used to be a Spanish teacher, and the truth is when a
language is your second one, you tend to get a little nervous when
speaking it since you don't know if you'll mess up, or what people
would say... as a matter of fact, its a big problem in schools is that
a lot of kids know how to speak in another language, but because of
this unfounded phobia of messing it up, they do tend to not talk
any... my advice would be just to practice speaking more... and if you
do get nervous, tell yourself not too... a lot of people don't know a
second language, and since you can speak another one, be proud of
yourself... people won't laugh, and if they do then you can brush it
off since you know that you are so much more talented since you can do
what they can't :)

Relax, and just let it flow, it will all come together :)

Mr.Design

Are you constructing the sentences from your first language and then
translating it into English?
Many people do that and it is a complete blunder!!! I am native in
Spanish I have an universitarian profficiency, it is not sensible to
translate my universitarian expression into English cause I do not
have the same skills.
If that is what are you doing try to think in English and to speak
without thinking in your first language terms. Of course complement it
with readings, chats with foreigners, tourists or friends, etc.
Good luck!!!